Schirjajew participated from 2001 to 2006 mainly in FIS races . At the U23 World Championships in 2006 in Kranj , he won silver in the skiathlon . In the World Cup he started for the first time at the Tour de Ski 2006/07 and finished there in 12th place. He achieved the fastest time in the final mountain pursuit. In February 2007 he won his first World Cup victory with the relay in Davos . At the subsequent World Championships in Sapporo he reached 11th place in free technique over 15 km . This result was withdrawn from him because a positive doping test became known on the last day of the World Championships. He was then banned for two years for EPO abuse. After the suspension had expired, he started again in the World Cup and again achieved the fastest time in the final pursuit at the 2009 World Cup Finals , finishing tenth overall. At the beginning of the 2009/10 season he won La Sgambeda . At the Tour de Ski 2009/10 he came in 29th place. At the following World Cup in Rybinsk he was third in the 30 km skiathlon. At the 2010 Winter Olympics in Vancouver , he finished 31st over 15 km freestyle. At the end of the season, he achieved 29th place in the 2010 cross-country skiing world cup finals in Falun . At the Nordic World Ski Championships in Oslo in 2011, he finished 41st in the 50 km mass start race. In the following years he mainly started in the Eastern Europe Cup . He achieved nine podium finishes and two wins. In the 2011/12 and 2012/13 seasons he took third place in the cup ranking. In March 2015 he was third in the Demino Ski Marathon over 50 km freestyle.